Postprandial effects of a polyphenolic grape extract (PGE) supplement on appetite and food intake: a randomised dose-comparison trial

Abstract

BackgroundThere is recent evidence that glucose delivered to the distal small intestine (SI) may stimulate the ileal brake and inhibit appetite. High polyphenolic grape extract (PGE) has been shown to inhibit α-amylase and α-glucosidase activity, two key enzymes required for starch digestion, in vitro. It is hypothesised to slow digestion and absorption of starch in the proximal SI such that glucose may be delivered distally into the ileum and suppress appetite. This study investigated the safety and efficacy of a PGE supplement, delivered within a capsule and consumed with a high-starch breakfast, on appetite ratings and ad libitum energy intake (EI) at a subsequent lunch meal.MethodsTwenty healthy, non-obese (BMI 18–28 kg/m2) male volunteers participated in a randomised, double blind, placebo controlled, three arm, cross-over study. Participants were administered (i) low dose PGE500 (500 mg), (ii) high dose PGE1500 (1500 mg), and (iii) matched placebo with a 2MJ high-starch breakfast (white bread); followed 3 h later by a single item buffet-style lunch meal (pasta and meat sauce). Outcome variables were feelings of hunger, fullness, prospective thoughts of food (TOF) and satisfaction assessed using visual analogue scales (VAS); and ad lib energy and macronutrient intake at the lunch meal.ResultsThere was no detectable effect of PGE500 or PGE1500 compared with placebo (all, time*supplement interaction, P > 0.05) on VAS-assessed hunger, fullness, TOF or satisfaction. There was also no evidence that PGE significantly altered ad lib energy or macronutrient intake at the lunch meal relative to placebo (P > 0.05). EI following PGE500 was +164 kJ higher than placebo (+5.3 %, P > 0.05); and EI following PGE1500was −51 kJ lower than placebo (−1.7 %, P > 0.05).ConclusionsWhilst well tolerated, there was no evidence that encapsulated low dose PGE500 or high dose PGE1500 consumed with a high starch breakfast meal altered postprandial hunger, fullness, TOF or satisfaction relative to a matched placebo. Nor was there evidence that either dose altered ad lib energy or macronutrient intake at an outcome meal.Trial registrationACTRN12614000041651

Glycaemic regulation, appetite and ex vivo oxidative stress in young adults following consumption of high-carbohydrate cereal bars fortified with polyphenol-rich berries

“…Importantly, studies demonstrating effects of polyphenol-rich foods on GLP-1 and/or ghrelin in a direction that would be expected to suppress appetite could not separate effects of polyphenols from the fibre and viscosity of the test meals (14,45) , which are both factors also thought to influence appetitemediating hormone responses (50) . In addition, a recent study found no acute effect of consuming 0•5-1•5 g of polyphenolrich grape seed extract on appetite (51) , despite the extract having been shown to inhibit α-amylase and α-glucosidase in vitro (52) , similar to the polyphenols used in the present study. Collectively, these findings do not support an appetite suppressing effect of berry polyphenols within the doses studied when fibre intake and viscosity are matched across fortified and non-fortified food products.…”

Appetite-Suppressing and Satiety-Increasing Bioactive Phytochemicals: A Systematic Review

“…Out of 32 analyzed studies, 16 (50%) did not report adverse events at all. In 10 of the remaining 16 trials, none of the tested plant extracts caused an adverse event [15,48,49,54,56,64,68,70,71,76]. Six studies [51,58,63,66,67,74] reported mild adverse events such as gastrointestinal distress (e.g., dyspepsia, flatulence, diarrhea, or constipation), skin rash, or headache.…”

“…In multiple studies that recorded the outcomes over several hours on just one or two days, respectively, participants were instructed to refrain from exercise 24 to 48 h before test day [28,51,60,61,62,65,75] and to arrive after an overnight fast at the test center [52,57,62,69,70,76,86]. The bioactive phytochemical was mostly taken with a standardized meal, varying from a breakfast meal with approximately 1150 kJ (275 kcal) [73] to a breakfast buffet with a total amount of approximately 32,962 kJ (7878 kcal) [61].…”

The effects of grape seed extract (Vitis vinifera) supplement on inflammatory markers, neuropeptide Y, anthropometric measures, and appetite in obese or overweight individuals: A randomized clinical trial

“…We demonstrated that appetite score changed negligibly in the GSE group in comparison to the baseline (~1%), although we did not find any significant differences between the two groups which is in line with previous studies. Shin et al indicated that high polyphenolic grape extract did not alter postprandial hunger or fullness in non‐obese subjects (Shin et al, ). In addition, Vogels et al observed that 300 mg grape‐seed extract (polyphenolics) containing 90% procyanidines can reduce 24‐hr energy intake by 4% while no effects on satiety was observed in normal and overweight individuals (Vogels et al, ).…”

“…In addition, polyphenols have beneficial effects against obesity through modulating inflammatory markers (Corrêa & Rogero, ) and grape components have been introduced as anti‐obesity agents that could lead to body composition improvements in animal or in vivo models ( Charradi et al, ; Moreno et al, ; Park, Park, & Cha, ) . Little is known about the effects of GSE supplementation on food intake and appetite in human (Hendrickson & Mattes, ; Shin et al, ; Vogels, Nijs, & Westerterp‐Plantenga, ). Furthermore, the potential anti‐obesity mechanism of GSE still remains unknown (Jeong, Jung, Cho, Youn, & Hong, ; Vogels et al, ).…”